This application claims the benefit of a Japanese Patent Application No.2000-256339 filed Aug 25, 2000, in the Japanese Patent Office, the disclosure of which is hereby incorporated by reference.
1. Field of the Invention
The present invention generally relates to designing methods, computer-aided-design (CAD) apparatuses and storage media, and more particularly to a designing method for designing a three-dimensional model having a part which changes shape before and after assembly, a CAD apparatus which employs such a designing method, and a computer-readable storage medium which stores a program for causing a computer to design a three-dimensional model by such a designing method.
2. Description of the Related Art
Conventionally, a CAD apparatus is used to design a three-dimensional model which is made up of a plurality of parts. In a case where the three-dimensional model is a printer, for example, an interference check is carried out to detect interfering locations which are generated when various parts forming the printer are automatically arranged and assembled. The interfering location refers to a portion where at least two parts overlap and interfere with each other. When such an interfering location is detected, an operator, that is, the designer, modifies the arrangement of the parts related to this interfering location based on an interfering volume, so as not to generate the interference, and then assembles the rearranged parts. Hence, the interference check is an important element of the designing of the three-dimensional model, from the point of view of improving the design quality.
The parts which are assembled include parts which are made of materials which change shape before and after the assembly. In other words, when a soft (or deformable) part is inserted between two hard parts and a thickness of this soft part before the assembly is greater than a predetermined value and a gap between the two hard parts after the assembly is set less than or equal to the predetermined value, the soft part will undergo resilient deformation.
However, the conventional CAD apparatus treats both the soft part and the hard part in the same manner. As a result, the part which actually changes shape before and after the assembly is treated with the shape before the change occurs.
For this reason, when the parts forming the three-dimensional model are automatically arranged and assembled, an interfering location which is generated on the CAD may not occur when the parts are actually assembled due to the resilient deformation of the soft part. In this first case, the interfering location generated on the CAD actually does not need to be recognized as an interfering location. On the contrary, even when no interfering location is generated on the CAD when the parts forming the three-dimensional model are automatically arranged and assembled, an interfering location may occur when the parts are actually assembled due to the resilient deformation of the soft part which causes the soft part to expand in one or more directions. In this second case, although no interfering location is generated on the CAD, it is desirable to recognize the interfering location which will actually occur.
In the first case, the interference check is carried out with respect to the interfering location which actually does not occur.
Consequently, the designer modifies the arrangement of the parts and assembles the rearranged parts although such modification and assembly are actually unnecessary or, the designer at least confirms whether or not it is necessary to modify the arrangement of the parts or the like. Therefore, there were problems in that the load on the designer becomes large, and that the designing efficiency becomes poor.
On the other hand, in the second case, the interfering location which will actually occur cannot be detected during an initial stage of the designing. For this reason, there were problems in that the load on the designer is even larger, and that the designing efficiency likewise becomes poor.
Accordingly, it is a general object of the present invention to provide a novel and useful designing method, CAD apparatus and compute-readable storage medium, in which the problems described above are eliminated.
Another and more specific object of the present invention is to provide a designing method, CAD apparatus and computer-readable storage medium which are capable of reducing the load on the designer and designing a three-dimensional model with a high designing efficiency.
Still another object of the present invention is to provide a designing method for designing a three-dimensional model having at least one part made of a material which changes shape depending on assembling conditions, comprising the steps of (a) automatically obtaining structural dimensions of the part in a deformed state after assembly, from structural dimensions of the part before the assembly, based on parameters including at least the assembling conditions, and (b) creating the three-dimensional model using the structural dimensions of the part in the deformed state. According to the designing method of the present invention, it is possible to reduce the load on the designer, and to design a three-dimensional model with a high designing efficiency.
A further object of the present invention is to provide a CAD apparatus for designing a three-dimensional model having at least one part made of a material which changes shape depending on assembling conditions, comprising a first section which automatically obtains structural dimensions of the part in a deformed state after assembly, from structural dimensions of the part before the assembly, based on parameters including at least the assembling conditions, and a second section which creates the three-dimensional model using the structural dimensions of the part in the deformed state. According to the CAD apparatus of the present invention, it is possible to reduce the load on the designer, and to design a three-dimensional model with a high designing efficiency.
Another object of the present invention is to provide a computer-readable storage medium which stores a program for causing a computer to design a three-dimensional model having at least one part made of a material which changes shape depending on assembling conditions, where the program comprises a first procedure which causes the computer to automatically obtain structural dimensions of the part in a deformed state after assembly, from structural dimensions of the part before the assembly, based on parameters including at least the assembling conditions, and a second procedure which causes the computer to create the three-dimensional model using the structural dimensions of the part in the deformed state. According to the computer-readable storage medium of the present invention, it is possible to reduce the load on the designer, and to design a three-dimensional model with a high designing efficiency.
Other objects and further features of the present invention will be apparent from the following detailed description when read in conjunction with the accompanying drawings.